Retractable road barrier

ABSTRACT

A safety barrier for road use comprises a barrier element ( 5 ) which can be displaced between an operative position, above the road surface, and an inoperative position, in which it does not substantially project above the road surface. Preferably provided is a number of sets of aligned barrier elements, rigidly connected to one another, the adjacent sets being connected together by articulated connecting structures ( 18 ) which enable one set of barrier elements ( 5 ) to be displaced between its inoperative position and its operative position without modifying the positions of the adjacent sets. In this way, one or more stretches of the barrier can be brought into the inoperative condition, leaving the adjacent stretches of barrier in the normal operative condition. The invention is particularly, although not exclusively, suited for the construction of traffic-divider barriers in road tunnels where it is necessary to eliminate the barrier rapidly in the event of an accident occurring.

The present invention relates to safety barriers for road use of thetype comprising at least one barrier element and a supporting structurefor supporting the barrier element, provided with means for anchoringthereof to the ground, wherein said supporting structure is movablebetween a first position, in which the barrier element is in anoperative position above the road surface, and a second position, inwhich the barrier element is in an inoperative position in which it doesnot substantially project above the road surface, wherein in saidinoperative condition the barrier element is received inside a trenchformed in the road surface, wherein the supporting structure includes atleast one supporting column articulated at one of its ends to a bracketfor anchorage to the ground and, at the opposite end, to the barrierelement, said supporting column being pivotable between an operativeupright position and an inoperative lowered position, and in which meansare provided for controlling rotation of said supporting column.

A road barrier of the above indicated type is disclosed in documentDE-A-34 20 503. In this known solution, more barrier elements areprovided which, when in the lowered position, are spaced apart from eachother, so that free spaces are defined therebetween which require theprovision of additional platforms in order to cover the trench whichreceives the barrier elements in the lowered condition. Moreover, inthis known solution, in case only some of the barrier elements arelowered into the inoperative position, interruptions are formed at theareas interposed between each lowered element and an adjacent raisedelement. Finally, the solution shown in the above indicated document hasa structure such that any operations for replacing a damaged barrierportion, for example due to a road accident, become lengthy andtroublesome.

The same drawbacks are encountered also in the barrier shown in documentFR-A-2 750 148. In particular, although this solution shows a barrierwith a connecting element which connects a retractable barrier elementto a non-retractable barrier element, it does not provide for aconnecting element between two barrier elements which are bothretractable, so that there are not ample possibilities to choose thebarrier portion which one wishes to retract. Furthermore, the barrier ofthis second known solution does not ensure a continuous surface bothabove and on the two sides of the barrier and moreover it has columnsfor supporting the retractable element which are directly articulated tothe walls of the trench in which the retracted element is received, sothat any operations for replacing a damaged barrier element are lengthyand costly.

The object of the present invention is that of providing a road barrierwhich is able to overcome all the above mentioned drawbacks.

In view of achieving this object, the invention provides a road barrierhaving all the features which have been indicated at the beginning ofthe present description and further characterized in that said safetybarrier comprises a succession of sets of one or more barrier elements,the barrier elements of each set being rigidly connected to each other,and adjacent sets of barrier elements being connected to each other bymeans of articulated connecting elements having variable length, whichenable a relative displacement in a vertical direction of any set withrespect to the other, while always defining a continuous upper surfaceand two side continuous side surfaces of the barrier in any position ofany set of barrier elements of the barrier.

Due to the above indicated features, there exists an ample flexibilityin the configurations which can be selected for the barrier, since anyone of the sets of barrier elements can be displaced from the operativeraised position to the lowered inoperative position, while the setsadjacent to the ends of the lowered set can be either kept raised orlowered, at will, the connecting elements between adjacent sets ensuringthe continuity of the upper surface and the two side surfaces of thebarrier in any case. Furthermore, since each set of barrier elements isconstituted by barrier elements whose supporting columns are articulatedto a bracket which is anchored to the ground, each of these sets forms aunit which can be easily removed and replaced.

A further object of the present invention is that of ensuring that thebarrier elements can be all moved to their lowered position even in caseof an absence of the electric main supply, which condition may well takeplace in case of an accident, or in case of a fire inside the tunnel.

In view of efficiently solving this problem, the barrier according tothe invention is further characterized in that a solenoid valve isprovided which can be activated in order to put a cylinder for raisingthe barrier element in a discharge condition, in order to cause loweringof the respective barrier element, and in that emergency electric supplymeans are provided for activating said solenoid valve in case of afailure in the main supply of electric current. In this manner, in anysituation of emergency in which the electric main supply has beeninterrupted, it is possible to cause an automatic lowering of thebarrier elements to their retracted position.

Further characteristics and advantages of the present invention willemerge from the ensuing description, with reference to the attacheddrawings, which are provided purely by way of non-limiting example andin which:

FIG. 1 is a schematic view illustrating a road tunnel in which the twotraffic lanes (in opposite directions) for motor vehicles are divided bya safety barrier according to the invention;

FIG. 2 is a side elevation of one portion of the safety barrier of FIG.1 in its operative condition;

FIG. 3 is a perspective view of an element of the barrier of FIGS. 1 and2 in its operative condition;

FIG. 4 illustrates a connecting element which rigidly connects twobarrier elements adjacent to one another;

FIG. 5 is a perspective view of an articulated connecting element whichconnects together two sets of barrier elements in such a way as toenable movement of one set with respect to the other;

FIG. 6 is a schematic side view which shows a connecting element betweentwo different sets of barrier elements in two different operatingconditions; and

FIG. 7 is a sectional view taken along the line VII-VII of FIG. 6.

In FIG. 1, the reference number 1 designates as a whole a road tunnelhaving two lanes 2, 3 for passage of traffic in two opposite directions,which are separated by a safety barrier 4 built according to theinvention.

The barrier 4 comprises an aligned succession of barrier elements 5consisting of metal channel section with reversed-U cross section andundulations for stiffening, if so required, the said barrier elementsbeing each carried by a set of three supporting columns 6. Each column 6has one end articulated in 7 (FIG. 2) to the respective barrier element5, and the opposite end articulated in 8 to an attachment elementanchored to the ground.

The barrier elements 5 are rigidly connected together in sets of anumber of elements (for example, three) by connecting elements 9consisting of reversed-U channel section, which are set on top of oneother and are bolted by means of screws 9 a (see FIG. 7) to the barrierelements 5. The ensemble consisting of three barrier elements 5 makingup each set can be displaced between its normal operating position, inwhich it projects above the road surface (FIG. 2), and a lowered,inoperative, position, which is reached by means of simultaneousrotation downwards of the columns 6 about their respective bottomarticulations 8 and in which the barrier elements 5 disappear inside atrench 10 made in the road surface. The movement of the barrier elements5 between an inoperative position and the operative position iscontrolled, for each set of three barrier elements 5 connected rigidlytogether by the connecting elements 9, by a single hydraulic cylinder 11having one end articulated to the ground and the opposite endarticulated to a bracket 12 (FIG. 3) of the central column 6 of the setof three columns 6 associated to the central barrier element 5 of theset of three barrier elements 5 rigidly connected together. Forstiffening purposes, the said central column 6 is provided with abracing arm 13. A plate 40 is set between each pair of adjacent columns6 (only one plate 40 being illustrated), which has both a stiffeningfunction and the function of partially closing the trench 10 when thebarrier is raised. The hydraulic cylinder 11 is supplied by a pump 14which is controlled by an electric motor 15, the assembly consisting ofthe motor 15 and the pump 14 being mounted inside a channel 16 (FIG. 3)anchored to the ground. Fixed to the said channel are also theattachments 17 which are provided in the trench 10 (see also FIG. 7). Inthis way, the entire module consisting of the channel 16 and all thecomponents illustrated in FIG. 3 can be readily and quickly replaced.

The system is provided with means for automatic control of lowering ofthe barrier in the event of failure of electric power supply (as in thecase of an accident in a tunnel). For example, a 12-V emergency electricpower generator may be envisaged which drives a solenoid valve thatcontrols the cylinder.

FIG. 4 is a perspective view which clearly illustrates the connectingelement 9 that rigidly joins barrier elements 5 to form a set of threeelements. FIG. 5 is a perspective view illustrating a connectingstructure 18 which is set between two adjacent sets of three barrierelements 5. The structure 18 comprises two portions of channel section18 a, 18 b which are articulated in 7 a, 7 b to two adjacent columns 6(see FIG. 6) and which are moreover connected together in an articulatedway by means of transverse pins 7 c. The articulation in 7 b is obtainedby engagement of the side pins in side slits 20 made in the sides of therespective barrier element 5. The articulation 7 c is also obtained bymeans of side pins which engage both the slits 20 made in the element 18a and the slits 21 made in the element 18 b.

Thanks to the arrangement described above, when the set of three barrierelements 5 that is on the left, with reference to FIG. 6, is lowered,with respect to the set of three elements that is on the right-handside, the connecting structure 18 moves from the condition illustratedwith a solid line to the condition illustrated with a dashed line. Inthis way, continuity of the barrier is ensured, and at the same time thepossibility is guaranteed for just a few portions of the barrier to belowered into the inoperative position, leaving the remaining portions inthe normal operating condition.

According to a further important feature of the invention, the fluidcylinder is of the single effect type, which causes raising of therespective barrier element when it is supplied with fluid underpressure, whereas it automatically returns to the conditioncorresponding to the lowering of the barrier element when its hydraulicchamber is connected to discharge. According to the invention, thischamber of the fluid cylinder can be connected to a discharge by meansof a solenoid valve which can be activated by an emergency electricsupply (such as a backup battery, or an emergency electric generator) incase the main supply is interrupted following an emergency situationsuch as in case of a fire within the tunnel. The barrier according tothe invention is thus able to provide a high degree of safety since itis automatically brought to the retracted condition in the abovedescribed emergency situations.

Finally, the elements of the barrier can also be used to carry anoptical guide. For instance, inside some or all the barrier elements itis possible to provide a duct made of transparent plastic material (suchas polycarbon) with a OLF film provided inside the duct, a light sourceat one end, for example constituted by a plurality of LED devices, and aclosing cover at the opposite end with a reflective film. The LED lightsource is supplied with a low voltage direct current and offers a highdegree of safety in the system as well as a low energy consumption. Theuse of this optical guide enables the forwarding of coloured lightsignals, if necessary intermittent, which are controlled by anelectronic control unit and have the purpose for instance of signallingthe proper safety spacing between each vehicle and the subsequent one,the safety speed and the stop areas for the vehicles which travelthrough the tunnel.

From the foregoing description it is evident that the idea underlyingthe invention is to provide a safety barrier that can be quickly broughtinto an inoperative condition in which it does not project above theroad surface, with the consequent advantages that have been mentioned atthe beginning of the present description. Of course, the structure andarrangement of the barrier elements that have been illustrated herein byway of example could be altogether different. The same applies to thedevices used for controlling movement of the barrier elements. A furtherpreferred characteristic of the invention lies in the characteristicdescribed previously, which regards the possibility of displacing onlyone portion of the barrier between the operative position and theinoperative position, without changing the positions of the adjacentportions. In addition, without prejudice to the principle of theinvention, the details of construction and the embodiments may varywidely with respect to what is described and illustrated herein purelyby way of example, without thereby departing from the scope of thepresent invention.

For example, It would also be possible that each lowerable barrier unitcomprises a single barrier element.

1-5. (canceled)
 6. A safety barrier for road use, comprising: at leastone barrier element, and a supporting structure for supporting at leastone barrier element, provided with means for anchoring thereof to theground, wherein said supporting structure is displaceable between afirst position, in which at least one barrier element is in an operativecondition above the road surface, and a second position, in which atleast one barrier element is in an inoperative condition in which itdoes not substantially project above the road surface, wherein, in saidinoperative condition, at least one barrier element is received inside atrench formed in the road surface, wherein the supporting structureincludes at least one supporting column articulated at one of its endsto a bracket for anchorage to the ground and, at the opposite end, to atleast one barrier element; said supporting column pivotable between anupright operative position and a lowered inoperative position, whereinmeans are provided for controlling rotation of said supporting column,wherein said safety barrier comprises a succession of sets of one ormore barrier elements, the elements of each set being rigidly connectedto each other and adjacent sets being connected to each other by meansof articulated connecting elements having a variable length, whichenable a relative displacement in the vertical direction of one setrelative to the other, while always defining a continuous upper surfaceand two continuous side surfaces for the barrier in any position of anyset of the barrier, and wherein said barrier element and saidarticulated connecting elements are in form of metal profiles having across-section in form of an inverted U, each having an upper wall andtwo side walls extending through a substantial portion of the height ofsaid supporting columns.
 7. Barrier according to claim 6, characterizedin that said means for controlling rotation of said supporting columninclude a fluid cylinder, a solenoid valve for connecting said fluidcylinder to a discharge, in order to cause lowering of the respectivebarrier element in its retracted position, and emergency electric supplymeans for activating said solenoid valve in case of an interruption ofthe electric main supply.
 8. Barrier according to claim 7, characterizedin that said means for activating the solenoid valve are able to becomeautomatically operative in case of an interruption of electric mainsupply.
 9. Barrier according to claim 6, characterized in that anoptical guide is associated to one or more elements of the barrier.